Further evaluation is necessary.
Is this the first time your periods are late? Or you have on and off history of irregular periods.
Most common causes of late periods are
Pregnancy ( you already checked, it is negative)
Hormonal imbalance (
thyroid,
prolactin, PCOS)
Residual ovarian cyst ( sonography will be required)
Use of Ipill ( emergency contraception)
Evaluation is needed to pin point a diagnosis and then treat it.
It's been more than 2 months, you should visit your doctor for further evaluation and appropriate treatment.
Next Steps
Online consultation for period problems and evaluation.